当我删除setButton()并按键时，会有正确的反应，但如果我添加setButton()，只有按钮有效，按键没有反应，这里会发生什么？
public class Sokaban extends JFrame implements ActionListener {
private static final long serialVersionUID = 1L;
JButton btnBack,btnFirst,btnNext,btnPrev,btnLast,btnSelect,btnMusic,btnReset;
JComboBox<String> cbMusic;
JMenuBar menuBar;
JMenu mnuOption,mnuSet,mnuHelp;
JMenuItem miReset,miPrev,miNext,miSelect,miExit,miBack;
JMenuItem miMusic1,miMusic2,miMusic3,miMusic4,miMusic5;
JMenuItem miHelp;
//music file
String sMusic[] = {
"eyes on me.mid",
"guang.mid",
"nor.mid",
"popo.mid",
"qin.mid"
};
//game panel
MyPanel mainPanel;
public Sokaban(int[][] samplemap){
super("Game 2017");
Toolkit toolkit = Toolkit.getDefaultToolkit();
Image image = toolkit.getImage("pic/p0.jpg");
//set icon
this.setIconImage(image);
Container c = this.getContentPane();
c.setLayout(null);
c.setBackground(Color.orange);
JLabel lblTitle = new JLabel("SOKABAN GAME",JLabel.CENTER);
lblTitle.setFont(new Font("",Font.BOLD,20));
lblTitle.setBounds(100,40,500,30);
c.add(lblTitle,BorderLayout.NORTH);
//put buttons
setButton(c);
setMenus();
mainPanel = new MyPanel(samplemap);
mainPanel.setBounds(60,120,450,450);
mainPanel.setFocusable(true);
mainPanel.requestFocusInWindow();
c.add(mainPanel);
setSize(720,720);
this.setLocationRelativeTo(null);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
//set button
public void setButton(Container c){
btnReset = new JButton("Reset");
btnBack = new JButton("Back");
btnFirst = new JButton("First");
btnNext = new JButton("Next");
btnPrev = new JButton("Prev");
btnLast = new JButton("Last");
btnSelect = new JButton("Select");
btnMusic = new JButton("Music");
JLabel lblMusic = new JLabel("Select Music");
c.add(lblMusic);
btnReset.addActionListener(this);
btnBack.addActionListener(this);
btnFirst.addActionListener(this);
btnNext.addActionListener(this);
btnPrev.addActionListener(this);
btnLast.addActionListener(this);
btnSelect.addActionListener(this);
btnMusic.addActionListener(this);
//cbMusic.addActionListener(this);
cbMusic = new JComboBox<String>();
cbMusic.addItem("default");
cbMusic.addItem("good");
cbMusic.addItem("music");
cbMusic.addItem("choose");
cbMusic.addItem("column");
btnReset.setBounds(600,100,80,30);
btnBack.setBounds(600,150,80,30);
btnFirst.setBounds(600,200,80,30);
btnNext.setBounds(600,250,80,30);
btnPrev.setBounds(600,300,80,30);
btnLast.setBounds(600,350,80,30);
btnSelect.setBounds(600,400,80,30);
btnMusic.setBounds(600,450,80,30);
lblMusic.setBounds(600, 500, 80, 30);
cbMusic.setBounds(600, 530, 80, 30);
c.add(btnReset);
c.add(btnBack);
c.add(btnFirst);
c.add(btnNext);
c.add(btnPrev);
c.add(btnLast);
c.add(btnSelect);
c.add(btnMusic);
c.add(cbMusic);
}
//set menu
public void setMenus(){
mnuOption = new JMenu("Option");
miReset = new JMenuItem("Reset");
miPrev = new JMenuItem("Previous");
miNext = new JMenuItem("Next");
miSelect = new JMenuItem("Select");
miExit = new JMenuItem("Exit");
miBack = new JMenuItem("Back");
mnuOption.add(miBack);
mnuOption.add(miReset);
mnuOption.add(miPrev);
mnuOption.add(miNext);
mnuOption.add(miSelect);
mnuOption.addSeparator();
mnuOption.add(miExit);
mnuSet = new JMenu("Setting");
miMusic1 = new JMenuItem("default");
miMusic2 = new JMenuItem("good");
miMusic3 = new JMenuItem("music");
miMusic4 = new JMenuItem("choose");
miMusic5 = new JMenuItem("column");
mnuSet.add(miMusic1);
mnuSet.add(miMusic2);
mnuSet.add(miMusic3);
mnuSet.add(miMusic4);
mnuSet.add(miMusic5);
mnuHelp = new JMenu("Help");
mnuHelp.setMnemonic('H');
miHelp = new JMenuItem("About us...");
mnuHelp.add(miHelp);
miBack.addActionListener(this);
miReset.addActionListener(this);
miPrev.addActionListener(this);
miNext.addActionListener(this);
miSelect.addActionListener(this);
miMusic1.addActionListener(this);
miMusic2.addActionListener(this);
miMusic3.addActionListener(this);
miMusic4.addActionListener(this);
miMusic5.addActionListener(this);
miHelp.addActionListener(this);
menuBar = new JMenuBar();
menuBar.add(mnuOption);
menuBar.add(mnuSet);
menuBar.add(mnuHelp);
this.setJMenuBar(menuBar);
}
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
if(e.getSource().equals(miHelp)){
String str = "COMP2911\n";
str +="Assignment3\n";
JOptionPane.showMessageDialog(this, str, "Help", JOptionPane.INFORMATION_MESSAGE);
} else if(e.getSource().equals(miExit)){
System.exit(0);
} else if(e.getSource().equals(btnReset)){
System.out.println("reset the game");
} else if(e.getSource().equals(btnBack)){
System.out.println("get to the back stage");
}
}
//game panel
public class MyPanel extends JPanel implements KeyListener{
/**
*
*/
private static final long serialVersionUID = 1L;
private int[][] oriMap;
private int[][] tempMap;
Toolkit kit = Toolkit.getDefaultToolkit();
Image mapimg[] = {
kit.getImage("pic/0.png"),
kit.getImage("pic/1.gif"),
kit.getImage("pic/2.png"),
kit.getImage("pic/3.png"),
kit.getImage("pic/4.gif"),
kit.getImage("pic/5.GIF"),
kit.getImage("pic/6.GIF"),
kit.getImage("pic/7.GIF"),
kit.getImage("pic/8.GIF"),
kit.getImage("pic/9.png")
};
public int[][] getOriMap() {
return oriMap;
}
public void setOriMap(int[][] oriMap) {
this.oriMap = oriMap;
}
public MyPanel(int[][] map){
readMap(map);
setSize(600,600);
this.addKeyListener(this);
//this.setFocusable(true);
// requestFocus();
// repaint();
}
public void readMap(int[][] map){
this.oriMap = map;
this.tempMap = map;
}
@Override
public void keyTyped(KeyEvent e) {
// TODO Auto-generated method stub
System.out.println("2222222");
}
@Override
public void keyPressed(KeyEvent e) {
// TODO Auto-generated method stub
System.out.println("1111111");
}
@Override
public void keyReleased(KeyEvent e) {
// TODO Auto-generated method stub
System.out.println("2333333333333");
}
@Override
public void paint(Graphics g){
for(int i = 0; i < 15; i++){
for(int j = 0; j< 15;j++){
g.drawImage(mapimg[this.tempMap[j][i]], i*30, j*30, 30,30,this);
}
}
}
}
}
答案 0 :(得分：-1)
由于您要将JPanel和JButton添加到JFrame，KeyListener只有在JPanel关注时才会生效。当您按下按钮时，JPanel会失去焦点（如果您从一开始就有多个组件，它就不会自动聚焦）。您应该将KeyListener添加到JFrame。